Question

The probability that it rains on any day during the first week of April is 0.2. The probability that it rains three days during the week is given by?

Answer 1

so ...

Answer 2

lets call the days, 1,2,3,4,5,6,7 .
P ( X = 1 or 2 or 3 or 4 or 5... ) = .2
we want P ( x = 1,2,3 or 1,2,4 or 1,2, 5 , etc )

Answer 3

i think we can set it up as a binomial problem. the probability of success of raining on any day is .2 . probabiliy of failure is .8 .
we want SSSFFFF and combinations thereof

Answer 4

P( rains any 3 days ) = 7C3 * .2^3 *.8^4

Answer 5

hey fletchnuts

Answer 6

hey!

Answer 7

hi, post away :)

Answer 8

3. Let U = {a, c, d, f, h, m, p, r, t, w}
A = {a, c, f, r, t}
B = {a, c, m, t}
C = {d, m, p, r, t}

Find:

a) (A' ∩ B) ∪ (A' ∩ C')
b) (A ∩ B ∩ C)'
c) (B ∪ C)' ∩ A
d) n (A)
e) n (A ∪ B)

Answer 9

a) , so you understand what complement is , and so forth? union , intersection

Answer 10

can you explain intersection?

Answer 11

you can think of A ' as the universe set minus A , in terms of set theory (removing elements that match )

Answer 12

ok so an example
A = { 1,2,3} ,
B = { 1 , 2 , 3,4}
A intersect B is { 1,2,3 } , what they have in common

Answer 13

a' is d,h,m,w?

Answer 14

ok gotcha

Answer 15

Let U = {a, c, d, f, h, m, p, r, t, w}
A = {a, c, f, r, t}
B = {a, c, m, t}
C = {d, m, p, r, t}

Find:

a) (A' ∩ B) ∪ (A' ∩ C')
b) (A ∩ B ∩ C)'
c) (B ∪ C)' ∩ A
d) n (A)
e) n (A ∪ B)

Answer 16

Supposing that
A = { 1,2,3} ,
B = { 1 , 2 , 3,4}
A union B = { 1 ,2,3,4}
A intersect B = {1,2,3}
A is a subset of B, but we can about subset later. that just means every element in A is also an element in B

Answer 17

U = {a, c, d, f, h, m, p, r, t, w}
A = {a, c, f, r, t}
B = {a, c, m, t}
C = {d, m, p, r, t}
A' = { h, m, p, w}
B' = { f,h,p,r,w}
C' =

Answer 18

sorry ive been working them out. is a) {h,m,w}?

Answer 19

c'= a,c,f,h,w?

Answer 20

yes

Answer 21

when you put U = {a, c, d, f, h, m, p, r, t, w}
A = {a, c, f, r, t}
B = {a, c, m, t}
C = {d, m, p, r, t}
A' = { h, m, p, w}
B' = { f,h,p,r,w}
C' =


is there supposed to be a "d" in both a' and b'?

Answer 22

yes sorry

Answer 23

alright just making sure i didnt miss something. not tring to call you out. lol

Answer 24

when you put U = {a, c, d, f, h, m, p, r, t, w}
A = {a, c, f, r, t}
B = {a, c, m, t}
C = {d, m, p, r, t}
A' = {d, h, m, p, w}
B' = { d,f,h,p,r,w}
C' =

Answer 25

sweet deal i think i got it now ill let you know if i get stuck!!!!

Answer 26

:D

Answer 27

can you help me with B)?

Answer 28

b) (A ∩ B ∩ C)'